This is the Trojan:WinCE/Redoc family description.
Variants in this family are Trojan that infect Windows Mobile devices and send SMS messages to premium rate phone numbers, without the user's consent. This results in abnormally high phone charges. Alert users may detect the presence of an infection by
This Trojan's behavior is reminiscent of the malicious dialers of yesteryear, except that the targeted device is now a mobiel device rather than a computer connecting to the Internet via a modem.
Redoc variants may arrive on the victim's device bundled together with a legitimate application; in which case, it launches the legitimate application to mask the fact the legitimate application's cab file has been infected.
Trojan:WinCE/Redoc is a .NET application for mobiles, and uses basic4ppc (a .NET port for Windows Mobile).
To perform its message sending routine, on execution some Redoc variants will read configuration parameters from a file named setups.dll, a text file that contains the following information:
- Name of the executable to be launched
- Number to which SMS messages will be sent
- Text to include in the SMS message
- Number of SMS messages to be sent
The steps the trojan follows for its sending routine is simply as follows:
- When executed, the Trojan launches the executable specified as the first argument of the setups.dll file.
- The phone number to send the messages to is computed from the second line of the setups.dll file.
- Each SMS message contains the same text, as configured in the 3rd line of the setups.dll file.
- The amount of SMS messages sent by the malware depends on the 4th line. This may be 1 or more.
Other Redoc variants have these parameters hard coded.